Improving energy efficiency is a growing concern with vehicles because of the need to improve fuel economy while assuring acceptable vehicle performance. The HVAC system in a vehicle uses a substantial amount of energy that impacts fuel efficiency.
An internal heat exchanger (IHX) may be included in a HVAC system to transfer heat from the hot liquid refrigerant passing from the condenser to the evaporator to the cool vapor refrigerant passing from the evaporator to the compressor. Including an internal heat exchanger in an HVAC system before the compressor may cause an additional concern because there is a potential for higher refrigerant temperature at the compressor inlet due to the heat added by the internal heat exchanger. Higher refrigerant temperature at the compressor inlet can have a negative impact on compressor durability.
A receiver/dryer may be included in HVAC systems to remove moisture and debris from the refrigerant after leaving the condenser. The receiver/dryer may also store refrigerant to assure the availability of liquid refrigerant for the thermal expansion valve.
A thermal expansion valve (TXV) may be included in HVAC systems to control the flow of refrigerant from the condenser to the evaporator based upon the temperature and pressure of the cool vapor refrigerant as it exits the evaporator.
Placing the IHX, TVX, and receiver/dryer components in the engine compartment of the vehicle may create potential issues with tube routing and leaking tube connections. Adding a receiver/dryer requires added space within the limited space available in the engine compartment
The above problems and other problems are addressed by this disclosure as summarized below.